Lighting device for identifying and marking traffic areas of airports

Abstract

A lighting device, capable of identifying and marking traffic areas of airports, comprises at least one semiconductor lamp and an electronic control circuit, which is connectable to an electrical AC supply network with constant current feed. For controlling the operation of the semiconductor lamp, the control circuit has a rectifier, which is connectable without a transformer to the electrical AC supply network. It further has an internal power supply, which is connected to the rectifier, for supplying the semiconductor lamp with an electric direct current. Furthermore, the voltage supply device ( 3 ) having electronic power factor correction means, by means of which voltage and current can be kept in phase in all operating states of the lighting device ( 1 ). It furthermore re-adjusts the input voltage from the electrical AC supply network to allow the current predefined on the AC supply network to flow in the event of a small power demand of the electronic control circuit.

What is claimed is: 
     
       1. A lighting device configured to identify and mark traffic areas of airports, said lighting device comprising:
 at least one semiconductor light source; and 
 an electronic control circuit, configured to be operably connected to an electrical AC supply network with constant current feed, said electronic control circuit being adapted to control operation of the at least one semiconductor light source, 
 wherein said electronic control circuit comprises:
 a rectifier configured to be operably connected, to the electrical AC supply network, 
 an internal power supply device operably connected to said rectifier and adapted to supply the at least one semiconductor light source with direct electric current, 
 the internal power supply device having an electronic power factor correction means, wherein said electronic power factor correction means is adapted
 (i) to keep voltage and current received by said internal power supply from the electrical AC supply network in phase in all operating states of the lighting device, and 
 (ii) to re-adjust said voltage from the electrical AC supply network to allow said current predefined by the AC supply network to flow in an event of a small power demand of the electronic control circuit, 
 
 
 a measuring device at a load side of the rectifier configured to generate an analog input signal, wherein said analog input signal is representative of strength of said current, and 
 a control unit operably connected to said measuring device and configured
 to receive said analog input signal, 
 to define desired brightness of the semiconductor light source based on said analog input signal, and 
 to activate a driver means defining a current flow through said semiconductor light source. 
 
 
     
     
       2. The lighting device according to  claim 1 , wherein the rectifier means includes a synchronous rectifier means. 
     
     
       3. The lighting device according to  claim 1 , wherein the electronic control circuit has current detection means configured to detect current flowing during the operation of the lighting device. 
     
     
       4. The lighting device according to  claim 3 , wherein the current detection means comprises a low-pass filter. 
     
     
       5. The lighting device according to  claim 1 , wherein the electronic control circuit has a temperature detection means adapted to detect temperature of the semiconductor light source. 
     
     
       6. The lighting device according to  claim 1 , further comprising a transceiver means configured to establish data communication between the lighting device and an external control center. 
     
     
       7. The lighting device according to  claim 6 , wherein the transceiver means is configured to establish data communication via the AC supply network.